1. When an orthotropic plate is loaded parallel to its material axes, it results only _____
a) Shear strains
b) Normal strains
c) Parallel strains
d) Uniform strains
Explanation: Orthotropic materials are a subset of anisotropic; their properties depend upon the direction in which they are measured. When an orthotropic plate is loaded parallel to its material axes, it results normal strains.
2. When the stresses are determined in an orthotropic material, then they are used to determine ____
a) Strains
b) Deformation
c) Factor of safety
d) Loads
Explanation: Factors of safety (FoS), is also known as safety factor (SF), is a term describing the load carrying capacity of a system beyond the expected or actual loads. Essentially, the factor of safety is how much stronger the system is than it needs to be for an intended load. After determining the stresses in orthotropic materials by using an appropriate failure theory we can find factor of safety.
3. Stress- strain law defined as ______
a) σ=D(ε-ε0)
b) σ=D
c) σ=Dε
d) σ=Dε0
Explanation: The relationship between the stress and strain that a particular material displays is known as that particular material’s stress–strain curve. It is unique for each material and is found by recording the amount of deformation (strain) at distinct intervals of tensile or compressive loading (stress).
4. E1 value of Balsa wood is ___
a) 0.125*106psi
b) 12.04*106psi
c) 23.06*106psi
d) 7.50*106psi
Explanation: A material’s property (or material property) is an intensive, often quantitative, property of some material. Quantitative properties may be used as a metric by which the benefits of one material versus another can be assessed, thereby aiding in materials selection.
5. Consider an Axisymmetric problem of which is having a radius of r, rotational angle θ and length l. Then r dl dθ is known as ____
a) Elemental volume
b) Element
c) Elemental surface area
d) Elemental surface
Explanation: Axial symmetry is symmetry around an axis; an object is axially symmetric if its appearance is unchanged if rotated around an axis. Surface element may refer to an infinitesimal portion of a 2D surface, as used in a surface integral in a 3D space.
6. The stress vector is correspondingly defined as ___________
a) σ=[σy,σz,Tyz,σθ]T
b) σ=[σy,σz]T
c) u=[u, w]T
d) T=[Ty,Tz]T
Explanation: The stress is expressed by the Cauchy traction vector T defined as the traction force F between adjacent parts of the material across an imaginary separating surface S, divided by the area of S.
7. Problems involving three- dimensional axisymmetric solids or solids of revolution, subjected to _____ loading.
a) Rotational
b) Two-dimensional
c) Three-dimensional
d) Axisymmetric loading
Explanation: Axial symmetry is symmetry around an axis; an object is axially symmetric if its appearance is unchanged if rotated around an axis. Surface element may refer to an infinitesimal portion of a 2D surface, as used in a surface integral in a 3D space.
8. All deformations and stresses are independent of _______
a) Co-ordinates
b) Number of nodes
c) Rotational angle, θ
d) Area
Explanation: The point around which you rotate is called the center of rotation, and the smallest angle you need to turn is called the angle of rotation. The angle of rotation is a measurement of the amount, the angle, by which a figure is rotated counterclockwise about a fixed point, often the center of a circle.
9. Revolving bodies like fly wheels can be analyzed by introducing _______ in body force term.
a) Gravitational force
b) Revolving force
c) Centrifugal force
d) Centripetal force
Explanation: The centrifugal force is an inertial force (also called a “fictitious” or “pseudo” force) directed away from the axis of rotation that appears to act on all objects when viewed in a rotating frame of reference.
10. The stress- strain relation is given as ___________
a) σ=D
b) σ=Dε
c) σ=ε
d) ε=Dσ
Explanation: The Hook’s law, states that within the elastic limits the stress is proportional to the strain since for most materials it is impossible to describe the entire stress – strain curve with simple mathematical expression, in any given problem the behavior of the materials is represented by an idealized stress – strain curve, which emphasizes those aspects of the behaviors which are most important is that particular problem.